1. Field
Embodiments of the present inventive concept relate to organic light emitting display devices, and to methods of driving the organic light emitting display devices.
2. Description of the Related Art
In an organic light emitting display device, a driving transistor included in each pixel may generate a driving current based on a data signal, and an organic light emitting diode (OLED) included in the pixel may emit light based on the driving current to display an image.
The driving transistor may have a hysteresis characteristic, whereby a response characteristic in a current frame varies depending on an operating state in a previous frame. Thus, even if the data signal having the same voltage level is applied to a plurality of driving transistors, driving currents generated by the driving transistors may be different from each other according to respective operating states in the previous frame. For example, even if the same data voltage is applied in a current frame to a first pixel representing a black color in a previous frame and to a second pixel representing a white color in the previous frame, the first and second pixels may emit light with different luminances in the current frame.
Techniques for preventing luminance non-uniformity caused by the hysteresis characteristics of the driving transistors have been researched. For example, in a conventional organic light emitting display device, driving transistors of respective pixels may be initialized to an on-bias state before the pixels emit light. Accordingly, all driving transistors may have the same response characteristic, and thus the luminance non-uniformity caused by the hysteresis characteristic may be reduced. However, in this case, degradation of the driving transistors may be accelerated because the driving transistors are turned on every frame, and a compensation operation for a panel deviation may be required to be performed separately from the initialization operation.